I never was able to get my B380 stabilized and often saw 70F drops in temps. RecTeq told me it was normal. I returned it and bought a 590.
I also see the variability in the 590 offset at different temperature ranges. I thought the offset issue was random so my solution has been to monitor...
The most important part of a log IMO is the "results" and "next time section." I'm a fairly new smoker and I have 24 cooks under my belt. To me I want my cooks to get better. The next time section helps me record the "lessons learned" like pull the Turkey breast at 160F (instead of 170F-too...
In a 55 gallon waterproof food grade blue barrel that has gaskets. Barrel cost me $15 on Facebook Marketplace. This way I can store pellets outside. Holds 240 lbs plus (6 40# bags).